Merge pull request #44012 from nosan

* pr/44012:
  Add more tests for SystemStatusListener and LogbackLoggingSystem

Closes gh-44012

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/logback/SystemStatusListener.java

@@ -38,7 +38,7 @@
  */
 final class SystemStatusListener extends OnConsoleStatusListener {
 
-	static final long RETROSPECTIVE_THRESHOLD = 300;
+	private static final long RETROSPECTIVE_THRESHOLD = 300;
 
 	private final boolean debug;
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/logback/LogbackLoggingSystemTests.java

@@ -42,6 +42,7 @@
 import ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy;
 import ch.qos.logback.core.status.ErrorStatus;
 import ch.qos.logback.core.status.InfoStatus;
+import ch.qos.logback.core.status.OnConsoleStatusListener;
 import ch.qos.logback.core.status.StatusManager;
 import ch.qos.logback.core.status.WarnStatus;
 import ch.qos.logback.core.util.DynamicClassLoadingException;
@@ -673,6 +674,18 @@ void logbackDebugPropertyIsHonored(CapturedOutput output) {
 		}
 	}
 
+	@Test
+	void logbackSystemStatusListenerShouldBeRegisteredWhenCustomLogbackXmlHasStatusListener(CapturedOutput output) {
+		this.loggingSystem.beforeInitialize();
+		initialize(this.initializationContext, "classpath:logback-include-status-listener.xml", null);
+		LoggerContext loggerContext = this.logger.getLoggerContext();
+		assertThat(loggerContext.getStatusManager().getCopyOfStatusListenerList()).hasSize(2)
+			.allSatisfy((listener) -> assertThat(listener).isInstanceOf(OnConsoleStatusListener.class))
+			.anySatisfy((listener) -> assertThat(listener).isInstanceOf(SystemStatusListener.class));
+		this.logger.info("Hello world");
+		assertThat(output).contains("Hello world");
+	}
+
 	@Test
 	void logbackSystemStatusListenerShouldBeRegistered(CapturedOutput output) {
 		this.loggingSystem.beforeInitialize();

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/logback/SystemStatusListenerTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.boot.logging.logback;
 
+import java.util.List;
 import java.util.function.Supplier;
 
 import ch.qos.logback.classic.LoggerContext;
@@ -31,6 +32,7 @@
 
 import org.springframework.boot.testsupport.system.CapturedOutput;
 import org.springframework.boot.testsupport.system.OutputCaptureExtension;
+import org.springframework.test.util.ReflectionTestUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.ArgumentMatchers.any;
@@ -49,6 +51,15 @@ class SystemStatusListenerTests {
 
 	private static final String TEST_MESSAGE = "testtesttest";
 
+	private final StatusManager statusManager = mock(StatusManager.class);
+
+	private final LoggerContext loggerContext = mock(LoggerContext.class);
+
+	SystemStatusListenerTests() {
+		given(this.loggerContext.getStatusManager()).willReturn(this.statusManager);
+		given(this.statusManager.add(any(StatusListener.class))).willReturn(true);
+	}
+
 	@Test
 	void addStatusWithInfoLevelWhenNoDebugDoesNotPrint(CapturedOutput output) {
 		addStatus(false, () -> new InfoStatus(TEST_MESSAGE, null));
@@ -91,15 +102,43 @@ void addStatusWithErrorLevelWhenDebugPrintsToSystemOut(CapturedOutput output) {
 		assertThat(output.getErr()).doesNotContain(TEST_MESSAGE);
 	}
 
+	@Test
+	void shouldRetrospectivePrintStatusOnStartAndDebugIsDisabled(CapturedOutput output) {
+		given(this.statusManager.getCopyOfStatusList()).willReturn(List.of(new ErrorStatus(TEST_MESSAGE, null),
+				new WarnStatus(TEST_MESSAGE, null), new InfoStatus(TEST_MESSAGE, null)));
+		addStatus(false, () -> new InfoStatus(TEST_MESSAGE, null));
+		assertThat(output.getErr()).contains("WARN " + TEST_MESSAGE);
+		assertThat(output.getErr()).contains("ERROR " + TEST_MESSAGE);
+		assertThat(output.getErr()).doesNotContain("INFO");
+		assertThat(output.getOut()).isEmpty();
+	}
+
+	@Test
+	void shouldRetrospectivePrintStatusOnStartAndDebugIsEnabled(CapturedOutput output) {
+		given(this.statusManager.getCopyOfStatusList()).willReturn(List.of(new ErrorStatus(TEST_MESSAGE, null),
+				new WarnStatus(TEST_MESSAGE, null), new InfoStatus(TEST_MESSAGE, null)));
+		addStatus(true, () -> new InfoStatus(TEST_MESSAGE, null));
+		assertThat(output.getErr()).isEmpty();
+		assertThat(output.getOut()).contains("WARN " + TEST_MESSAGE);
+		assertThat(output.getOut()).contains("ERROR " + TEST_MESSAGE);
+		assertThat(output.getOut()).contains("INFO " + TEST_MESSAGE);
+	}
+
+	@Test
+	void shouldNotRetrospectivePrintWhenStatusIsOutdated(CapturedOutput output) {
+		ErrorStatus outdatedStatus = new ErrorStatus(TEST_MESSAGE, null);
+		ReflectionTestUtils.setField(outdatedStatus, "timestamp", System.currentTimeMillis() - 300);
+		given(this.statusManager.getCopyOfStatusList()).willReturn(List.of(outdatedStatus));
+		addStatus(false, () -> new InfoStatus(TEST_MESSAGE, null));
+		assertThat(output.getOut()).isEmpty();
+		assertThat(output.getErr()).isEmpty();
+	}
+
 	private void addStatus(boolean debug, Supplier<Status> statusFactory) {
-		StatusManager statusManager = mock(StatusManager.class);
-		given(statusManager.add(any(StatusListener.class))).willReturn(true);
-		LoggerContext loggerContext = mock(LoggerContext.class);
-		given(loggerContext.getStatusManager()).willReturn(statusManager);
-		SystemStatusListener.addTo(loggerContext, debug);
+		SystemStatusListener.addTo(this.loggerContext, debug);
 		ArgumentCaptor<StatusListener> listener = ArgumentCaptor.forClass(StatusListener.class);
-		then(statusManager).should().add(listener.capture());
-		assertThat(listener.getValue()).extracting("context").isSameAs(loggerContext);
+		then(this.statusManager).should().add(listener.capture());
+		assertThat(listener.getValue()).extracting("context").isSameAs(this.loggerContext);
 		listener.getValue().addStatusEvent(statusFactory.get());
 	}